The 4 1/2 year intervention study entitled Building Preventive Group Norms in Urban Middle Schools proposes to develop, conduct and evaluate a new, group norms-based approach to drug and sex-risk prevention with 7th and 8th grade students in the New Haven Public Schools. Specific aims are: (1) to incorporate a norms-based approach to adolescent drug and sex risk prevention, using principles and facilitation practices based on social construction theory and cooperative education, into an existing 7th and 8th grade classroom curriculum which emphasizes problem-solving skills for risk avoidance; (2) to test the efficacy of the new approach as measured by increases in drug and sex risk prevention norms and decreases in self-reports of exposure to peers' drug and sex risks, and own drug and alcohol use and unprotected sex, against a standard approach, using a pre-post experimental design with three post-intervention observation points (7th, 8th, 9th grades); (3) to conduct an intervention integrity study to assess standardization of the implementation and to identify and reduce potential sources of intervention bias; and (4) to manualize the intervention for further testing and dissemination. In Year 1, focus groups with students and interviews with teachers will be conducted, and existing curriculum rewritten to reflect both the intervention theory and the specific needs of the target population. In the 7th grade, the new intervention will be piloted in Year 1 and implemented in Year 2. In 8th grade, piloting will occur in Year 2 and implementation in Year 3. Outcome data will be collected at the end of each year using the Social and Health Assessment Instrument (SAHA) and a pre-post curriculum assessment instrument assessing change in group skills (group problem solving, conflict resolution and norms building) and individual norms and self-efficacy skills, individual and group target skills risk identification, perceptions of exposure to risk and self-efficacy risk exposure. Program staff will provide feedback to instructors to promote implementation integrity and evaluation staff will utilize observational methods to examine intervention integrity in 7th and 8th grade intervention years. Years 4 and 5 will be utilized to collect the final outcome assessment data, to analyze and triangulate data and to finalize curriculum and publications.